U.S. equities rose on Tuesday as the Federal Reserve kicked off a two-day monetary policy meeting.

The Dow Jones industrial average posted its 41st record close of the year, rising 39.45 points to 22,370.80. Verizon and Goldman Sachs contributed the most to the gains.

The gained 0.1 percent to a record of 2,506.65, with telecommunications and financials leading advancers. The Nasdaq composite advanced 0.1 percent and also posted a record close of 6,461.32.

The three major indexes had posted intraday highs on Monday.

Major U.S. Indexes: DJIA, NCOMP, SPX

The Fed is not expected to raise rates following its meeting. However, many market participants believe the central bank will announce the unwinding of its $4.5 trillion portfolio.

"They've kind of laid out the principles for the balance-sheet reduction process, but I expect to see that more formalized," said Eric Stein, co-director of global income at Eaton Vance.

The U.S. central bank amassed most of its massive balance sheet as it tried to bring the economy back to life following the financial crisis.

"This is going to be unprecedented and every central bank in the world will be watching how" the Fed accomplishes this, said Quincy Krosby, chief market strategist at Prudential Financial. "But investors will also be looking for clues about whether we'll get another rate hike in December."

The Fed has already raised interest rates twice this year and it expects to hike once more before year-end. Market expectations for a December rate hike rose to 58.3 percent on Tuesday on strong imports data.

Tension between the U.S. and North Korea has escalated recently. Last week, the isolated Asian nation launched a missile that flew over Japan before landing in the sea.

The launch took place after the U.N. Security Council unanimously imposed a ban on North Korea's textile exports and capped its crude oil imports.

However, "a new war on the Korean Peninsula seems very unlikely at this time," said Paul Christopher, head global market strategist at the Wells Fargo Investment Institute, in a note last week.

"The South Koreans we spoke with said they did not worry about a nuclear attack, and they widely dismissed a preemptive U.S. attack on North Korea," Christopher said. "We heard the same thing in China and in Japan, mainly because they perceive a low potential reward with a high risk."

Investors also kept an eye on tax-reform prospects, after Sen. Bob Corker told reporters that GOP lawmakers had reached a tentative tax reform-budget deal. Wall Street has been waiting for clarity on tax reform since Trump won the president.

The market's reaction to the news, however, was muted.

"The market is waiting for something more concrete at this point before really responding," said Tim Alt, director of rates and currencies at Aviva Investors. "And with the Fed on tap for tomorrow, nobody wants to make any big bets."